Question

All non-metals are bad conductors of heat and electricity.
A. True
B. False

Answer 1

Non-metals are not less dense and so they don’t have enough free electrons to pass electricity efficiently. In nonmetals electrons are held tightly, And no free electrons are allowed to move freely.

Complete step by step answer:
We know that the elements that can readily give up electrons and can carry electric current because their electrons can flow freely are known as metals. Whereas the elements that tend to gain electrons instead of giving electrons up they cannot carry electric current, they try to hold their electrons in their body so that they cannot flow these types of materials are known as non-metals.
As non-metals do not allow free flow of electrons hence a body does not heat up easily and in case of metal as free flow of electron is allowed the body gets heated up quickly as heated electrons move inside the body. The same happens with electricity in metals the free electrons carry charges which allow flow of electricity and in non-metal the electron does not move so no flow of electricity is allowed.
Therefore option B, true is the correct option.

Note:
There are some exceptions like we know that metals are always hard and good conductors of electricity, but mercury is a metal which is liquid in nature and in case of poor conductors of electricity, Bismuth and tungsten are two metals which are poor conductors of electricity. Generally we know non-metallic structures are soft and tend to break, but however one of the strongest materials in the earth that is diamond is a non metal.